//我这里取的字段是Float类型的，你们需要缓存自己对应能进行计算的字段类型

Integer dateCode = Integer.parseInt(DateUtil.format(new Date(),"yyyyMMdd"));

        List<WyScore> list = xxxxMapper.selectList(new QueryWrapper<WyScore>().eq("xxxx","参数1").eq("zzzz","参数2"));

        //取同一个值类型集合写法1

        List<Float> countFs = list.stream().map(WyScore::getCountScore).collect(Collectors.toList());

        //求和 写法1

        Double countF =list.stream().collect(Collectors.summingDouble(WyScore::getCountScore));

        //求和 写法2

        Double countF2 = list.stream().mapToDouble(WyScore::getCountScore).sum();

还有一种，看不懂也没用Float的运用就没写了